Modern consumers often carry a large number of various cards and other items, including credit cards, debit cards, licenses, merchant loyalty or membership cards such as frequent flyer cards or preferred customer cards, insurance cards, and other items. The task of carrying and keeping track of these items is burdensome, and it is desirable to find a way to reduce the number of items that a consumer needs to carry. Furthermore, some of these kinds of items require use of an identifying number, often called a “personal identification number” or PIN. Remembering a large number of PINs is also burdensome, and it would be desirable to find a way to reduce the number of PINs that the consumer must remember.